Characterization and Purification of Herbicide Naproanilide Receptor from Tobacco Mesophyll Callus

Abstract

Herbicide naproanilide receptor proteins in tobacco mesophyll callus were isolated and characterized. The reaction between naproanilide and its receptor proteins is a specific binding with dissociation constant K d = 1.8 × 10-7 M. The optimum conditions for the binding reaction are 0−4 °C at pH 5.8−7.8 for 30−45 min. Purification of naproanilide receptor proteins on a chromatograph with Sepharose 6B gel filtration, DEAE-Sephacel ion exchange and NOP-ε-l-lysine-Sepharose 4B affinity columns in sequence revealed the molar mass 48 kDa. Purified naproanilide receptor exhibited no stimulation on RNA synthesis, and the results indicated that the receptor may be only a carrier for absorption and translocation of plant hormone but cannot enter nuclei for RNA synthesis and regulation of gene expression. Keywords: Naproanilide; receptor protein; binding activity; chromatography; purification method